The changing trend in drug abuse patterns and drug users seeking treatment has resurfaced the importance of psychological factors in the treatment of substance abuse. The major objective of this 18 month proposal is to provide empirical information bearing upon this issue. Three interrelated studies focus on the specific aims of the proposal. (1) To determine the extent to which the psychological profiles of substance abusers admitted for treatment in TCs has changed across a 10 year period; (2) to clarify the range and type of psychological dysfunction or disability among substance abusers as assessed through psychiatric diagnosis; (3) to develop a typology of substance abusers in treatment along dimensions of psycho-social dysfunction. In this regard, a brief monograph will be compiled describing these psycho-social subgroups of clients to be utilized by the TC modality for assessment and treatment planning. The general method involves secondary analyses of 3 existing data sets, 2 developed on Phoenix House populations and the third on a consortium of 7 other therapeutic communities (TCA). These contain an extensive and comprehensive array of social and psychological variables describing 3 different admission cohorts, 1974 (Phoenix House), 1979 (TCA), and 1984 (Phoenix House). A new data collection is proposed on clients seen at admission but not entering residential treatment (N=350). All of these will obtain a full psychological battery, and half a psychiatric diagnoses, those who do not enter treatment (N=75) and those who enter the non-residential modality (N=75). The proposed studies will offer firm hypotheses for later comparative studies of clients in other treatment settings and will clarify the relevance of mental health concepts and of psychotherapeutic approaches to treatment of substance abuse.